thrombus vs. embolus

thrombus vs. embolus: What’s the difference?

An embolus is a blood clot that stays where it forms—either in a blood vessel or in a chamber of the heart. A thrombus is some kind of mass (such as a detached blood clot or air bubble) that travels in the bloodstream and can obstruct blood vessels. A case of clotting that’s the result of an embolus is called an embolism (such as a pulmonary embolism), while the formation or presence of a thrombus is called thrombosis (such as deep-vein thrombosis).